The present invention relates to a substance applying apparatus. It has long been known, with respect to the application of substances, to hold in readiness a first component of the substance in a first chamber and an additional component of the substance in a second chamber and to effect mixing of the two components in the two chambers by applying a pressure such that a structure adapted to maintain the two components separate from one another is broken through to thereby permit mixing of the two components within the two chambers. An example of such an arrangement is disclosed in DE-AS 2 024 402.
Substance applying apparatus having application elements have, in any event, long been known, whereby, for example, such a device is disclosed in DE-GM 92 189 49. Via side holes in an inner tube, a fluid connection between the inner space of the inner tube and the inner space of the outer tube is produced. This arrangement is suitable for cosmetic products. If the application scenario requires storage of the substance component in the inner space of the inner tube separate from the substance component in the inner space of the outer tube, however, this solution is less suitable.
It is further known in DE-OS 44 158 54 to provide a mixing and application capsule for dental purposes. With this arrangement, the substance components are united with one another by the puncture, with a sharp element, of a film between the substance components.
Numerous other substance applying apparatus are known. Thus, for example, it has been proposed to maintain an application element in a submerged condition in a fluid, whereupon, upon application of a downward pressure on the fluid retaining container, an additional fluid is permitted to flow thereinto in the manner of an overspill action, in order to thereby place in readiness the substance which is to be applied. This arrangement requires, in any event, two separate sealing off systems so that a not inconsiderable effort is required to configure the arrangement. A plurality of sealing locations brings with it, in any event, a correspondingly large susceptibility to damage and storage instability.
It has further been proposed, in German Patent Application 199 56 705.0, to dispose an application element with a wetting body partially in an inner tube and to dispose the inner tube in an outer tube. By means of an application of pressure on the application element, a fluid connection between the inner space of the inner tube and the inner space of the outer tube is produced. The arrangement basically offers a good and simple sealing off of the two substance components to be held in readiness for eventual combination together to form the substance to be applied. To be sure, the outer tube must be produced with a somewhat elastic material in preparation for the deployment of a sealing lip, in order to ensure a fluid tight disposition of the sealing lip between the inner tube and the outer tube. On the other hand, it is important that the substance to be received in the inner space of the outer tube can also be stored therein in a secure manner for a long time. In order to achieve this goal, a substantially large wall thickness must be provided.
In certain applications, additionally, solvents such as acetone, ethyl alcohol and so forth are deployed as the substance components. Such solvents exhibit an exceptionally high vapor pressure and diffuse through the outer tube, even if the walls thereof have a substantially large wall thickness.
To be sure, it has become conventionally known to limit a high vapor pressure by the addition of additional coatings such as, for example, a metallic coating. The problem with this arrangement is that double-coated materials are problematic due to the processing and disposal issues involved therewith and, moreover, a complete blocking off of the vapor pressure is not possible. To be sure, the metallic coating can also be applied on an interior surface. In that event, however, the metallic coating extends over the sealing lips disposed therein so that the sealing effect is thereby reduced. At the same time, the application of a metallic coating adds to the production expense of the substance applying apparatus, whereby the production costs of such devices in connection with the realization of a single dose unit is of particular importance.
The present invention offers a solution to the challenge of providing a substance applying apparatus which is cost favorable in its production and which is operable to apply a substance, with the substance applying apparatus being suitable as well for storing the to be applied substance components therein for more than one year and for applying substances having a high vapor pressure.
In accordance with the present invention, it is especially advantageous that the formation of the inner tube of a soft material permits the sealing off function to be ensured solely by the inner tube itself and permits the formation of the outer tube from a non-yielding and highly non-porous material. This arrangement is cost favorable for the reason that the wall thickness of the outer tube can be reduced while, however, storage stability is available due to the improved vapor pressure sealing off ability.
The desired softness and deformability of the inner tube, in accordance with the present invention, permits flexibility in the material choices as well as the configuration choices of the inner tube. If a deformation element exerts a one-sided radial force on the bottom of the inner tube or on a region adjacent to the bottom of the inner tube, the inner tube collapses thereat, at least partially, so that the sealing off between the inner tube and the outer tube is lost in the desired manner.
In accordance with the present invention, it is preferable if the sealing lip is formed in an annular shape in the region adjacent the bottom of the inner tube and extends outwardly. The wall of the outer tube can thereby be formed, in the interior of the outer tube, with a completely smooth surface up to the location of the deformation element.
In accordance with the present invention, it is particularly advantageous if the bottom of the inner tube is configured to be significantly thin. Due to a one-sided and massive wedge, which forms the deformation element, a correspondingly thin bottom of the inner tube can be deformed in the application operation, even if the material properties of the substance components in the inner tube and the outer tube differ only slightly from one another. To this extent, the formulation of a tube to be xe2x80x9csofterxe2x80x9d is also to be understood to include the concept of being xe2x80x9cmore yieldingxe2x80x9d and, as required, the inner tube can alternatively be comprised of a substantially hard material, it being understood that the prerequisite therefor is that the desired sealing off function must still be ensured.
In accordance with a particularly favorable embodiment of the substance applying apparatus of the present invention, the deformation element or the deformation body is disposed on the side of the inner wall of the outer tube and extends in a progressively sharper manner in the direction toward the bottom of the inner tube. The radial depth of the deformation element increases continuously in a direction toward the bottom of the outer tube and, in the region of the inner tube, approaches substantially zero radial depth. In this manner, the resistance of the inner tube to insertion along the deformation element is substantially small and the deformation of the inner tube occurs in a gradual manner as the inner tube is inserted downwardly.
The deformation element, on its outer side can either be ball shaped or have a cutting portion. In the configuration of the deformation element with a cutting portion, it is also possible to exploit the hard material properties of the outer tube such that the bottom of the inner tube, or especially, one or more sealing rings, are normally cut. In this arrangement, the openings in the inner tube can be dispensed with, whereby it is to be understood that suitable desired deformation elements can be deployed in order to produce a fluid connection between the inner space of the inner tube and the inner space of the outer tube.
It is also possible to configure the sealing ring as an O-ring which is disposed in a groove on the inner tube. In this arrangement, the cutting portion can cut the O-ring. The O-ring retracts along its longitudinal extent and thereby makes available for fluid passage therethrough a region in which the fluid can flow through the openings into the inner space of the inner tube.
It is to be understood that the groove should be so configured that the cutting operation of the cutting portion is not hindered but, instead, is facilitated.
Even in the event that an asymmetric deformation element is preferred, it is possible without additional structure to provide two deformation bodies disposed in opposed arrangement to one another and cooperating together to pinch the inner tube and thereby produce a space or gap in the form of an overflow channel between the inner space of the inner tube and the inner space of the outer tube. It is additionally further possible, without additional structure, to configure the deformation body in a suitable desired configuration, whereby it is preferred that an inner corner extends immediately adjacent the deformation body which permits an overflow to flow therealong toward the bottom of the inner tube.
The application element comprises a wetting body which, as required, is either already provided with a reaction substance, or is provided with a reaction substance before the application operation. The wetting body can be configured in a suitably desired manner as, for example, a brush or a foam body which is connected or coupled to a stock of the application element.
It is also possible that the application element is itself separately deployed and thus a different combination of substance components can be placed in readiness for subsequent mixing together to form the substance to be applied, whereby advantage can be taken of the fact that the substance applying apparatus can also be sealed off without an application element therein.